Control device for milling machines



Nov. 3, 1931. 1 c. POTTER CONTROL DEVICE FOB MILLING- MACHINES 3 Sheets-Sheet l Filed DeC- 8 1921 Nov, 3, 1931.

J. C. POTTER CONTROL DEVICE FOR MILLING MACHINES Filed Deo.y

5 Sheets-Sheet 2 www Nev.2 3, 1931.

J. CI` POTTER DEVICE FOR MILLING MACHINES CONTROL s sheets-sneek s Filed Dec.'

MNHN@ Patented Nov. 3, 1931 Y. Y Y l l,

unirse STATES! PATENT OFFICE JAMES CHARLES POTTER, 0F PAWTGKET,` RHODE ISLAND CONTROL DEVICE Fon MILLING imoia'iinns Application filed December 819'21. Serial No. 520,884.

My invention relates to milling machines In the annexed drawings; of the type such as that forming the subject Fig. is a view in side elevation with parts of my Patents No. 1,060,705,issued May 6/13, in section of portion of a milling machine and No. 1,186,681, issued June 13/16, in which embodying my invention, 5 a plurality of work tables or supports mount- Fig. 2 is a'front elevation thereof; 55 cd on or carried by a rotatable support or Figx is a plan View of the automatically turret are employed, the work on the revOperating control mechanism;

spective tables or supports bein-g in turn pre- Fig. t is' a detail view in plan showing the sented for action of the milling tool. In ma- Valve chest; l0 chines of this type having, as in the case of Fig 5 is a Vertical section thereof; 60

the machines illustrated in suoli patents, two Figs 6 and .7 are detail views of the @am Work tables op Suppofts Situated on Opposite and rollerdevice to hold the lock bolt out of sidesof the turret aXis, the cycle of operation CGltt wltli the turret. consists in first unlockingthe turret, next re- Rfelrhg 110W 1n detail to the drawings, it I5 Volvng it through half revolution to Shift will be seen that I employ a frame that in 65 on@ Work table from position for the milling clude's a hollow base or pedestal, 10, upon 'too-1 t0 Cut the Work 1113011 Such table and Silill@ lOp 0f WlllCll 1S HlOuIltBdrt UITG, l1., that inultaneously to shift the other work table SU'PPGTS 1113011 its Vupper side two side by side from such position so that Yfinished work, if SllClGS 01 WOrk l 10lders, 12, each in its guides, l thereon, may be removedand new'worl ap- 1 3', the tWO slid@ bemin' thus 011, Opposite 70 plied; next the stopping and locking of the sides ofthe Vertical axis of rotation of the turret with the work tables in such. interturret and I'eClplOCabie beneath the milling changed position; and finally the feed movei001 .SgplIlCll 1 Cile .0f the slides or work nient of the work. The object of my present hOldlS belg in the operation of the maif. mvomon, generally Statecp is to incl-oase the chine beneath the cutter and the other beyond 75 out-put of milling machines of this typ@ the cutter at the front of the machine for which in the embodiment of my invention that Nady aCQGSS of the workmen thereto to rel shall hereafter describe is accomplished by DOV'flI-llShGd WOIk 01V1 apply new work. effecting the indexing operation or the inter- AS 1H the milling' machine ShOWH ill H15 3i" change of positions of the work tables or supabove mentioned patents, the rotation or in- 80 ports automatically so that theoperator may flexing of the turret is effected by power taken devote his time and labor to the operations from the'driving shaft and the feed of the of loading and unloading the tables and by work is also edected by power taken from automatically changing the rate of feed so the driving shaft, but as the gear @cuneo 35 that the feed is faster than the regular outtions by which the ndexg and feed 'm0 V5 Emil mt@ 0 feed Wham Cuttmg ,1S not bemg tions are produced does not in itself form an UORE? 51S m lh@ Case of Several Places of Work essential partiof my invention, any detailed spaced 13pm? on the saine mp1@ or Work Sup' description and illustration thereof is unl port, wnen tne spaces oi intervals between the necessary Sumo@ to Say that the. gear com l f l' th tool tiin beino' lost .i

plages 0 Worx pass e e t nections for in exiio a t l i L A of course, when the travel is at the cutting d D d eed mdude Slut rate oi feed when no work is being cut. am? Clutches A iockng bolt is Provided Another object of my invention is to effect which enters holes in the turret to secure'the either or both of the automatic actions just tuFet at the endof each half fvolutlon A7 mentioned by devices that are at once simple, Winch' lockmg bolt after being Wlthdl'RWIl quicl: and otherwise efficient. For the at- 'folltur'et h ole to allow rotation of the imminent of thoso objoots my invention oonturret is restrained inV withdrawn position sists in a construction described by or included Ulll the half TBVOlutOIl O the turret is acwithin the terms or scope of theappended coinplished, whereupon the bolt moves into lo claims. i locking Vengagement therewith. Y 100 Cil rEhe movement of the locking bolt to release the turret, and of the clutches that control the indexing of the turret and the feed of the work tables is produced by fluid pressure mechanism that comprises a cylinder and a piston and valve-operating devices carried by the work tables, so that at predetermined points in the travel of said tables the fluid pressure devices will act, such a mechanism having the qualities of simplicity, compactness, and quickness of action.

For the release of the locking bolt and the throw of the clutch for indexing, a single fluid pressure device is employed that consists of a cylinder, 15, mounted at one end upon a bracket, 16, within the pedestal., and a piston, 1'?, the portion of the piston rod, 18, outside the cylinder having a longitudinal slot, 19, one end of which engages a cross pin, 20, in one arm of a bell crank lever, 21, mounted on a rock shaft, 22, the other arm of the bell. crank lever being adapted to act on the lever, 230, connected with the lower end of the vertical turret-locking bolt, 23. The bell crank lever has an arm', 24, Whose free end is situated to engage the lever, 25, which controls the turret indexing clutch, and which lever, 25, is on a rock shaft, 26. Compressed air or other fluid under pressure may enter the cylinder, 15, through a port, 27, at one end thereof, for moving the bell crank lever, 21, in the direction to withdraw the locking bolt, d3, and, when such bolt is withdrawn from the turret to engage the clutch of the turret indexing` mechanism, the return movement of the piston is accomplished by a spring device, which, as shown, consists of two coil springs, 28, on opposite sides of the cylinder, which at one end engage a cross bolt, 29, on the piston rod, and at the other end being attached to studs or pins, 30, projecting from the cylinder side. The slotted connection between the piston rod and the bell crank lever, 21, is provided because a treadle, 31, mounted on the rock shaft, 26, is employed to enable the release of the locking bolt and the operation of the indexing clutch independently of the fluid pressure device which may be necessary, for example, in setting up jobs and under circumstances when compressed air or other fluid under pressure is not available. rlhe treadle lever, 31, passes beneath the lever arm, 24, and acts to raise it.

A pipe, 32, connects the cylinder port, 27, with a valve box, 33 (to which air is sup plied by a pipe A from a suitable source not shown), on the front of the machine near the top of the pedestal, 10, which contains a spring-seated ball valve, 34, which normally prevents the flow of fluid under pressure to the cylinder, 15, and which is movable from its seat to allow the flowl of Huid under pressure to the cylinder, 15, by the engagementJ with it of a vertically slidable plunger, 35,

whose Lipper end projects from the valve bon in position to be engaged by the lower end of a rod or pin, 36, slidable in a bracket, 37, secured to the side of the turret, 11, the upper end of said rod or pin, 36, being in the path of a dog, 38, adiustably secured in a T-slot in a dog bar, 39, secured to the outer side of the work table or slide, 12, it being understood that each slide, 12, has a similar equipment of dog bar and dog, and that the turret, at diametrically opposite points, has duplicate brackets, 37, and sliding pin equipment, these duplicate devices being in succession by the half revolution of the turret brought into cooperative relation with the valve box devices, which, as will be presently pointed out, include valves and operating pins that control clutches that determine the rate of feed of the work, the feed during cutting being at one rate and the feed, when no cutting is being done, as when a space or interval between pieces of work on the table is pre` sented opposite the cutter being at faster rate.

The fluid pressure device for controlling the rate of feed of the work or work tables comprises a cylinder, 40, mounted within the pedestal, 10, near the bottom thereof, and piston, 4l, the piston rod, 42, being connected at one end with a lever, 43, that is connected with the clutch device that controls the feed, and which lever preferably has a handle, 44, to enable the movement of the feed clutches to be effected by hand should that be desired as when no fluid under pressure is available or there are other reasons making hand movement desirable. The cylinder, 40, has near each end a port so that movement of the piston in both directions may be ef fected by fluid pressure admitted alternately at opposite ends of the cylinder. In the arrangement shown in the drawings, when compressed. air or other fluid under pressure is admitted below the piston, the fast feed clutch is disconnected and the slow feed motion is produced, while when pressure is admitted above the piston, the fast feed gearing is put in operation. A pipe, 45, connects the lower end of the cylinder, 40, with the valve box, 33, in which is a valve similar to the ball valve, 34, and which valve may be unseated by a vertically slidable plunger, 46, which is adapted to be depressed by a pin. 47, in the bracket, 37, when a slow feed dos".l 48, carried by the dog bar, 39, engages said slidable pin. F rom the. port opening into the upper end of the cylinder, 40, a pipe, 49, leads to the valve box, 33, which has a ball valve similar to the ball valve, 34, for controlling the flow of compressed air or fluid under pressure to the upper end of the cylinder, 40, which ball valve is unseated by a slidablc pin. 50, in the valve box whose upper end is in the path of a slidable pin, 51, mounted in the bracket, 37, and whose upper end is in the path imams' of a fast feed dog, 52,.m'ountedon the dog bar, 39. In order that each dog may operate only its own valve mechanism, the ends. of

, the slidable' pins which they strike are situat- V jected to no pressure which would lift them out of their guide openings in the bracket.

The three valve-operating plungers are `alike excepting the plunger, 36,- which controls the release of the turret locking bolt which has a lateral extension, 53, at its top with which the slidable pin, 36, continues in engagement as the turret revolves, for a sufficient length of time to assure the locking bolt being held withdrawn from the turret bv the action of the cylinder, 15, and its piston, until the customary cam plate, 54, en gaga roller, 540, on the upper end of a rod, 541, pivoted to a lever, 542, that engages an arm, 231, of the lever, 230, positively holds the locking bolt disengaged from the turret until the half revolution of the turret has been accomplished, and the reengagement of turret and locking bolt must take place. A spring, acting on the lever, 542, yieldinglyr A' holds the roller, 540, against the cam, 54. By

the time indexing is completed and the locl ing bolt should reengage the turret, the piston, 17, in the cylinder, 15, has been retracted by the spring device acting upon the piston rod, and thereby the end of the slot, 19, which acts upon the cross pin, 20, of the lever, 21, is withdrawn from engagement with such cross pin, so that the locking bolt is free to snap or spring into locking engagement with the turret the instant the indexing motion is completed. During the indexing operation, the pressure of the cylinder, 40, is cut loff and the exhaust is open the -exhaust connection not being shown.

While, as before stated, thegear connections for indexing and the feed motions are not essential part of my invention, perhaps a brief description of such portions thereof as appear in the drawings may be. desirable.

For indexing the turret has a gear, 55, with which meshes a pinion, 56, on the upper end cf a sleeve, 57, whose lower end has a clutch collar, 58, with which a clutch face, 59, on a gear, 50, slidably mounted on the same shaft, 61, on which the pinion is mount` ed may be engaged and thus rotate the pinion sliding movement of the gear, 60, being effected by a clutch arm, 62, on a vertically movable rod, 63, which is engaged by the lever, 25, and thereby moved. The gear, 60, is in mesh with and receives motion from a gear, 64, on the same shaft, 65, with a wormV wheel 66,which is enOfaUedb aworm 67 on 7 e? :n y a a a shaft,y68, that receives motion from the main driving, shaft of the machine.

There are two shafts which receive motion from the main drivingV shaft of the machine either one of which at a time may drive the feed mechanism, one of which shafts p roduces the slow working feed and the other the faster feed. The shaft, 69, for producing the slow working feed has a worm, 70, which meshes with a worm wheel, 71, on a vertical shaft, 72, which is concentric with the turret uponrwhich is loosely mounted a gear, 73, which meshes with a gear, 74, that drives a train, 75, by which the feed motion of each slide, 12, is produced. The gear, 73, by a clutch device/76, receives its motion from the shaft, 72 ,to impart the slow feed, while to impart the fast, feed, the gear, 73,V is con nected with and driven by a gear, 77, loose on the shaft, 72, and when driven, as about to be explained, revolves the gear, 7 3, faster than it is revolved by its clutch connection with the shaft, 72, such lclutch connection, 76,'permitting` the overrunning of the,gear,

73, from the shaft, 72. The gear, 77, is drivf en by ameshing gear,i7 8, on a vertical shaft, 7 9, which has a bevel gear, 80, that meshes witha bevel gear, 81, on a shaft, 82, upon which is a spur gear, 83, in mesh with aV spur gear, 84, on a shaft, 85, which by a clutch,

86, is 'adapted to be connected with and disconnected from the main driving shaft of the machine and when connected therewith drives the shaft, 85,;at the rate of speed necessary to produce the fast feed of the work tables. Ihe clutch, 8G, is under the control of the lever, 43, whichV may be actuated by the air cylinder, 41. The movement of the clutchobeing `produced by the longitudinal movement of the shaft, 85, which is connected with the lever, 4.8, by a gear segment, 87, on the lever, 43, and a rack, 8S, on a sleeve, 89, on the shaft, 85.

What I claim is:

l. In a milling machine, the combination of a plurality of reciprocating independent work-holders either of which may be presented to position for operation with the same tool, automatic means for interchanging the working relation of such work# `holders with the tool, and a control device for such'automatic means receiving movement from one of such reciprocating workholders.

2. In a milling machine, the combination of a plurality of reciprocating independent work-holders either of which may be presented to position with the same tool, automatic means for interchanging the working relation of such work-holders with the tool, and a control device for such automatic means receiving movement Vfrom one of such reciprocating work-holders, each of such work-holders having such a control device.

3. In a milling machine, the combination of a turret, a plurality of independent Workholders carried by said turret eccentric to the axis of rotation thereof, and automatic means to index the turret including a movable control device connected with each of said Worl--holders, either of said ivork-hold ers being presentable to position for operation with the same tool.

4. In a milling machine, the combination of a turret, a pair of slides mounted on the turret eccentric to the axis of rotation there of, and automatic indexing means comprising a dog carried by each of said slides.

5. In a milling machine, the combination of a turret, a pair of slides mounted on the turret eccentric to the axis of rotation thereof, automatic indexing means comprising a dog carried by each of said slides, and a single operating mechanism with which said dogs successively coact.

(i. In a milling machine, the combination of a slide, means for imparting motion to said slide, a fluid pressure mechanism for operating such means comprising a cylinder and a piston, and a member receiving movement from the slide that controls the supply of Huid pressure to said cylinder.

7. In a milling machine, the combination of a turret, a pair of reciprocating slides situated on opposite sides of the axis of rotation of the turret, automatic mechanism for varying the rate of feed of such slides, and automatic turret indexing mechanism.

8. In a milling machine, the combination of a turret, a pair of reciprocating slides situated on opposite sides of the axis of rotation of the turret, automatic mechanism for Varying the rate of feed of such slides, automatic turret indexing mechanism, and devices to control the operation of both such mechanisms, moving with said slides.

9. In a milling machine, the combination of a moving member of the machine, a plurality of Work receiving surfaces arranged for successive cooperation With the cutter, and means to control the operation of such nember comprising coacting parts, one of which is stationarly mounted and the other, in duplicate, is carried by said Work receiving surfaces, such duplicate parts being successively presented for coact-ion with the sta- ,ionary part.

10. In a. milling machine, the combination of a base, a Work table supporting turret mounted on such base, turret indexing means, feed mechanism, and fluid pressure operating devices controlling said indexing means and said feed means comprising a valve box i mounted on the base and a plurality of valve operating devices mounted on the turret.

11. In a milling machine, the combination of a Work table carrying turret, turret indexing mechanism, turret locking means, and a single Huid pressure operated device op- JAMES CHARLES POTTER. 

